FR2763462A1 - MULTIMODE COMMUNICATION DEVICE AND METHOD FOR OPERATING A MULTIMODE COMMUNICATION DEVICE - Google Patents

Abstract

A communication method and device (102) providing multimode communication with a plurality of autonomous communication systems comprising a first communication system (104) and a second communication system (106). The resources are dedicated to communication on the respective communication systems. In order to minimize production costs, resources are shared anywhere between communication in the respective modes. A system supervisor (304) assigns priorities, schedules, and controls communication between the communication device and the autonomous communication systems.

Description

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  MULTIMODE COMMUNICATION DEVICE AND METHOD FOR

  OPERATION OF A MULTIMODE COMMUNICATION DEVICE

  The present invention relates, in general, to communication devices. More particularly, the present invention relates to multimode communication devices and operating methods

  such communication devices.

  Multimode communication devices are communication devices configured for communication like radio communication in more than one communication mode. For example, such modes of communication include digital and analog transmission, different frequency bands for communication, and communication according to different communication protocols. Examples of such protocols are the Advanced Mobile Telephony Service (AMPS), the Digital Cellular Service of North America according to J-STD-009, the 1900 MHz Standard of Minimum Mobile Station Performance based on PCS IS -136 and the J-20 STD-010, the Standard at 1900 MHz of Minimum Performance of Mobile Station based on PCS IS-136 ("1IS-136"); Code Division Multiple Access Radiotelephone Service (CDMA) according to provisional standard 95 EIA / TIA, Compatibility Standard Mobile Station / Fixed Station for Dual Mode Broadband Spectrum Cellular System ("IS-95") ); the Satellite System for Mobile Communication ("GSM"); and satellite protocols such as that proposed by Iridium, L.L.C. ("Iridium"; Iridiums is a trademark and service mark of Iridium, 30 L.L.C.). A common communication system provides communication in one of these modes for an area

  limited geographic. A multimode communication device can use one or more of these modes for communication.

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  Existing multimode radiotelephones include certain cell phones. For example,

  IS-136 and IS-95 cell phones can operate in both analog and digital mode. Cell phones according to the IS- standard

  136 are dual-band communication devices by the fact that they operate in a first band of

  frequencies near 800 MHz and in a second frequency band around 1900 MHz. Such radiotelephones10 communicate with a single type of communication system in different modes.

  Such previous radiotelephones are restricted by the limited geographic coverage of the system. When the radiotelephone moves to a new area beyond the limits of the system, the radiotelephone service is no longer available. Even if other systems provide service in the new area, unless that service is compatible with the radiotelephone, the radiotelephone cannot communicate with the system. In addition, system service20 may not be available for some time. Even if other (incompatible) systems provide a service

  in the same area, the radiotelephone cannot be used.

  We are considering a new type of radiotelephone capable of operating on autonomous communication systems.

  Autonomous communication systems are communication systems that are independent but can overlap over their geographic coverage areas. Then, in a particular area, a radio telephone of this new type can communicate with a ground system such as a GSM system and with a satellite system such as an Iridium system. In a different area, the

  radiotelephone can communicate with a GSM system and an IS-95 system.

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  Communication according to several autonomous communication systems differs from usual communication in a single system having several modes. In such systems, a mobile station such as a radio telephone5 communicates with several fixed base stations in the communication system. The base stations in turn communicate with a network control unit or a mobile telephone switching office which coordinates the system and ensures communications flow from one base station to another and from one mode to another. In autonomous communication systems, the respective systems are autonomous in that there is little or no intercommunication between the two systems. Communication is not possible between systems. A mobile station for use in multimode communication with autonomous systems must adapt to these limitations. In addition, there is constant research in the field of communication devices to minimize the cost of production of such devices. A common way to reduce production costs is to eliminate

  duplicate components by reusing a single component for different applications. For example, in dual mode radio sets according to IS-136 and IS-95 standards, it is known to use a single antenna for the operating modes, both analog and digital.

  Other shared hardware resources include voltage controlled oscillators and other frequency synthesizer components, digital signal processors, and receive and transmit authorizations. For economic viability, the

  multimode communication of the future will have to exploit this concept of shared resources while being able to communicate with several autonomous systems.

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  Thus, there is research in the field of art a multimode communication device and a method of

  operation of such a device solving these problems.

  The features of the present invention are

  set out in particular in the appended claims. The invention, in conjunction with these objects and advantages

  additional, can be better understood with reference to the following description, taken in conjunction with the accompanying drawings, in the various Figures o similar numerical references 10 designate identical elements and on which:

  Figure i is a block diagram of a communication device and a plurality of communication systems; Figure 2 is a flow diagram illustrating the operation of the communication device of Figure 1; Figure 3 is a block diagram of the communication device of Figure 1; Figure 4 is a flow diagram illustrating the operation of the communication device of Figure 3; Figure 5 is a flow diagram illustrating the operation of the communication device of Figure 3; and Figure 6 is a flowchart illustrating the operation of a communication system and the

  communication device of Figure 1.

  Referring to Figure 1, a communication device 102 can operate on a plurality of communication systems comprising a first communication system

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  communication 104 and a second communication system 106. In the illustrated embodiment, the first communication system 104 comprises a first base station 108, a second base station 110, a third base station5 and a communication unit network control 114. The second communication system 106 likewise comprises a first base station 115, a second base station 116, a third base station 118 and a system control unit 120. Each communication station base in each communication system provides radio communication with mobile stations such as the communication device 102 in a fixed geographic area adjacent to the base station. The network control unit in each communication system controls the communication between mobile stations and the base stations of the communication system and provides a link between

  communication with the public switched telephone network (PSTN).

  In the illustrated embodiment, the second communication system 106 is autonomous with respect to the first communication system 104. The communication systems are autonomous in that they are independent of each other. For example, there is little or no communication between the communication systems25 and their timing is not synchronized. No communication passage is planned between the two

  communication systems. Each system ignores the other. The communication device 102 communicates independently with each system.

  While two communication systems are illustrated in Figure 1, there may be any number of communication systems serving the geographic area in which the communication device 102 is located. This may include satellite communication systems such as the system Iridium and

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  ground systems such as AMPS systems, GSM systems, IS-136 systems, IS-95 systems and others. Likewise, communication systems can operate in different frequency ranges such as GSM at 900 MHz and GSM at 1800 MHz. Likewise, while the first communication system 104 and the second communication system 106 are illustrated as ground systems, it is understood that either each or both can be satellite systems with satellites in

  orbit or geosynchronous performing the functions of base stations.

  The communication device 102 comprises an antenna 122, a first transmitter / receiver 124, a second transmitter / receiver 126, a synthesizer 132 comprising a voltage-controlled oscillator 134, a control unit 136 comprising a memory 144, a user interface 138 including a memory 146, a speech processor

  and a battery 142. The components of the communication device 102 are housed in a housing 160.

  In the illustrated embodiment, the communication device is a multimode portable radiotelephone capable of operating in a plurality of communication systems comprising the first communication system 104 and the second communication system 25 106. A first operating mode corresponds to that of a first radiotelephone system and a second operating mode corresponds to that of a second radiotelephone system. Optionally, the first mode of operation corresponds to operation in a first frequency range and the second mode of operation corresponds to operation in a first frequency range.

second frequency range.

  The first transmitter / receiver 124 generally includes a transmitter 150 and a receiver 152 coupled to

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  antenna 122 for radio communication with the first communication system 104 of the plurality of communication systems. The first transmitter / receiver 124 includes hardware and software elements specially adapted5 for operation according to the communication protocol (AMPS, GSM, IS-136, IS-95, Iridium, etc.) used by the first communication system 104 and in the frequency band (eg, 800 MHz, 1900 MHz, etc.) used by the first communication system 104. The first transmitter / receiver 124 may likewise include a microprocessor or other processor and stored program instructions . An embodiment of such a transmitter / receiver can be easily carried out using known techniques. The first transmitter / receiver 124

  then provides the first operating resources of the communication device 102 according to a first mode.

  Likewise, the second transmitter / receiver 126 comprises a transmitter 154 and a receiver 156 coupled to the antenna 122 for radio communication with the second communication system 106 of the plurality of communication systems. The second transmitter / receiver 126 includes hardware and software elements specially adapted for operation according to the communication protocol used by the second communication system 106 and in the frequency band used by the second communication system 106. The second transmitter / receiver 126 may similarly include a microprocessor or other processor for operation in response to the stored program instructions. The second transmitter / receiver 126 then supplies the second operating resources of the communication device.

  102 according to a second mode, the second mode being autonomous with respect to the first mode.

  Synthesizer 132 generates oscillation signals required for the operation of the first transmitter / receiver

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  124 and the second transmitter / receiver 126. The oscillation signals are modulated in the transmitter 150 of the first transmitter / receiver 124 and in the transmitter 154 of the second transmitter / receiver 126 to respectively transmit information to the first communication system. 104 and the second communication system 106. The oscillation signals can be modulated to tune the transceivers on particular channels in their assigned frequency bands. Several voltage controlled oscillators like VCO 134 can be used, especially when multimode capability

  of the communication device 102 includes dual band or multiband operation.

  The control unit 136 controls the operation of the communication device 102. The control unit 136 can be implemented, for example, in the form of a microprocessor which can operate in response to programmed instructions stored in the memory 144 The program instructions can be stored in other places accessible to the control unit such as the first transmitter / receiver 124 and the second

  transmitter / receiver 126 and memory 146 of user interface 138.

  The user interface 138 includes hardware and software elements required for the operation and control of the communication device 102 by a user. Examples include a data interface for exchanging data with other equipment, a keyboard, a display, a microphone, and a speaker or earphone. The user interface 138 likewise includes software for controlling the

  hardware, software stored in memory 146.

  The speech processor 140 includes a speech processing circuit and software for processing

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  of speech. The speech picked up by the microphone of the user interface 138 is processed, for example, by digital coding and is transported to the transmitter 150 of the first transmitter / receiver 124 or the transmitter 154 of the second transmitter / receiver 126 for a transmission according to the communication protocol of the respective communication system. Similarly, the coded speech received by the receiver 152 of the first transmitter / receiver 124 or by the receiver 156 of the second transmitter / receiver 126 is processed in the speech processor 140 to extract the speech carried by the communication system. The floor is

  then supplied to the speaker of the user interface or to other destinations (such as a memory for storing a voice call message) in the communication device 102.

  According to the present invention, the antenna 122, the synthesizer 132, the VCO 134, the user interface 138, the speech processor 140 and the battery 142 form shared resources required for the operation of the communication device 102 in conjunction with the first resources (that is to say the first transmitter / receiver 124) according to the first mode and with the second resources (that is to say the second transmitter / receiver 126) according to the second mode. Parts of the first transceiver 124 and the second transceiver 126 may be combined to form additional shared resources. The two transceivers can be fully combined as a shared resource. Control unit 136 forms a resource manager for selective assignment of shared resources in response to the

  operation of the communication device 102 according to the first mode and according to the second mode.

  In an exemplary embodiment, the communication device 102 includes a radiotelephone

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  and the first resources include a first communication circuit, a first transmitter / receiver 124, for radio communication with a first remote transmitter / receiver, such as a third base station 112, in a first communication system 104. The second resources a second communication circuit, a second transmitter / receiver 126, for radio communication with a second remote transmitter / receiver, like the third

  base station 118, in a second communication system10 106.

  In the illustrated embodiment, the second transmitter / receiver 126 is housed in a detachable module 148. The detachable module 148 can be detached from the housing and replaced by other modules similar to the detachable module 148. For greater ease, the detachable module 148 may include a subscriber identity module (SIM) card. The other modules according to this

  The invention contains transceivers that can operate in different modes such as different communication protocols or on different frequency bands.

  The detachable module 148 allows a user of the communication device 102 to adapt the components of the communication device 102 to future communication systems encountered by the user. As an example, the second transmitter / receiver 126 in the detachable module 148 can be selected to provide service in the particular systems encountered by the user. For example, for a trip to Europe, the user will select a GSM module as the detachable module 148. For a trip to the United States, the user will select an IS-95 module. In addition, the first transceiver 124 may be a transceiver for use in a satellite radiotelephone system such as the Iridium system. The first transmitter / receiver 124 (in the illustrated embodiment) is not removable and the satellite service

  provides a service available via satellite as a backup when a local service via the detachable module5 148 is not available.

  When more than one communication system is available, the communication device 102 must assign priority to its use of the communication systems. A priority can be based on a number of factors such as system cost, specified local system, desire to move, etc. The unit of

  command 136 analyzes the availability of the system and makes access to the system priority, as will be described in more detail below.

  Figure 2 illustrates a block diagram of the operation of the communication device 102 of Figure 1. On the block diagram of Figure 2, it is considered that a system of the plurality of communication systems serving the geographical position of the communication device 102 is un20 preferred system and that the others are non-preferred systems. A system may be preferred for any reason including the cost of access, quality of service or the availability of service features. It is further considered that the communication device 10225 defines a priority A and a priority B. Priority A applies when a communication circuit such as the first transmitter / receiver 124 or the second transmitter / receiver 126 actively uses , the shared resources of the communication device 102 and cannot be interrupted. Priority B applies when a communication circuit wishes to use the resources

  shared but cannot be interrupted at any time.

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  The process begins in Step 200. In Step 202, the communication device 102 determines whether the preferred system is active. This can be achieved, for example, by testing reception of the broadcasting of the control channels by the base stations in the preferred system. If the preferred system is not active, the command goes to Step 214. If the preferred system is active, the communication device 102 places in Step 204 the transceiver for the non-preferred system in a state idle free line. In free line, the transmitter / receiver cannot use shared resources. In Step 206, the communication device 102 establishes communication in a first communication system, the preferred system, using a first communication circuit like the first

  transmitter / receiver, and a shared communication resource of the communication device.

  Beginning with Step 208, the communication device searches for interruptions in operation in the preferred system to begin operation on a non-preferred system. In Step 208, the communication device 102 checks a request from the transmitter / receiver for the operation of the non-preferred system. If such a request is received, the command goes to Step 222. If no such request is received, the communication device 102 determines in Step 210 whether a scheduled operating time for the non-preferred system has passed. Examples of times of planned operation are the assigned time slots30 used in TDMA communication systems and the interval call mode specified for CDMA IS-95 systems. Then, the communication device 102 detects a communication request on a second communication system such as the non-preferred system, the second communication system being autonomous with respect to

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  at first. If no such time has arrived, the

  communication device 102 determines in Step 212 whether communication on the preferred system is completed. If so, the operation stops. If not, operation 5 returns to Step 206.

  If in Step 208 or in Step 210, the communication device detected a transfer of interrupt condition request to the non-preferred system, the communication device determines in Step 222 if a priority A has been requested by the preferred system. If so, communication on the preferred system cannot be interrupted and the request for operation on the non-preferred system must be postponed. If priority A has not been requested, the communication device 102 inactive in Step 224 the first communication with the preferred system. The transmitter / receiver for the preferred system is placed in the inactive state and control is transferred to Step 214. The communication device 102 establishes a second communication on the second communication system using a second communication circuit and the device's shared communication resource

  Communication. The communication device 102 begins its operation on the non-preferred system.

  In Step 216, during operation on the non-preferred system, the communication device 102 determines whether there has been a request for operation on the preferred system. Such a request could likewise correspond to a planned operating time for the preferred system, such as a pre-assigned time interval or an interval call mode interval. In response to this interruption, the communication device 102 determines in Step 218 whether the transceiver for the non-preferred system has requested priority A. If yes, the communication on the non-preferred system cannot be interrupted and the system operation request

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  preferred should be deferred. The command returns to Step 214. If priority A has not been selected, the command goes to Step 204. If in Step 216, no request for operation on the preferred system is received, la5 command continues at Step 220 where the communication device 102 determines whether the communication on the

  non-preferred system is completed. If so, the process ends. If not, control returns to Step 214 for later communication on the non-preferred system.

  It will be noted that the operation can vary by modifying the priority assignment to the communication systems and by defining priority A and other priorities. For example, preferred additional systems can be defined, in conjunction with priorities such as the first preferred system and the second preferred system. Optionally, priority C (and others

  priorities) can be set to control access to other systems.

  Figure 3 illustrates an optional block diagram of the communication device 102 of Figure 1. Figure 3 is intended to present different functional blocks for controlling the communication device. As illustrated in Figure 3, the communication device 102 includes hardware 300, a user interface 302, a system supervisor 304, a plurality of system control units including a first system control unit 306, a second system control unit 308 and a third system control unit 310, and an operating system 312. The communication device 102 likewise includes a hardware abstraction layer 314. In the embodiment illustrated, user interface 302, system supervisor 304, first system controller 306, second system controller 358, third system controller 310,

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  operating system 312 and hardware abstraction layer 314 all represent program instructions for controlling a single microprocessor, such as control unit 136, of the communication device 102. Hardware 300 represents all of the hardware components of the communication device 102 comprising

  the control unit 136, the first transmitter / receiver 124 and the second transmitter / receiver 126, the synthesizer 132, the battery 142 and the hardware for the user interface 138.

  The user interface 302 corresponds to the control instructions of the user interface hardware (keyboard, display, etc.) of the communication device 102. For example, the user interface 302 recognizes pressures on the keyboard as indicating a user entry of a telephone number to call or the withdrawal of a voicemail message. In other examples, the user interface 302 interprets messages received from a communication system. These messages include a "ring" signal causing the user interface 302 to produce

  a warning to the user of an incoming call or a short text message causing the user interface 302 to display the text on the display.

  The system supervisor 304 provides priority control for access to the various communication systems available to the communication device. The system supervisor 304 arbitrates the use of the shared resources of the communication device 102. For example, the system supervisor 304 determines whether the communication device 102 calls on a communication system and if so, prevents an interruption by another system . System supervisor 304 coordinates the plurality of control units

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  system for multimode operation of the device

communication 102.

  The first system control unit 306, the second system control unit 308 and the third system control unit 310 form a plurality of system control units, each system control unit controlling the transmitter / receiver of the communication device 102 in communication with one or more respective transmitters / receivers remotely in an autonomous communication system. The first system control unit 306, the second system control unit 308 and the third system control unit 310 are the program instructions required for implementation of the communication protocol defined for each of the first, second and third communication systems. More or less system units can be used as required. In one example, the first system control unit 306 corresponds to the protocol for a satellite communication system such as the Iridium system, the second system control unit 308 corresponds to the protocol for a GSM system and the third system control unit 310 corresponds to the protocol for an IS-136 system. When the communication device 102 attempts to communicate with any of these systems, the system supervisor 304 activates the system control unit suitable for controlling the hardware 300 of the

communication device 102.

  The operating system 312 is the operating system of the microprocessor which controls the operation of the communication device 102. For example, if the microprocessor is a 68HCll microprocessor available from Motorola Inc., Schaumburg, Illinois, the operating system 312 is the instruction set of the

68HCll microprocessor.

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  The hardware abstraction layer 314 corresponds to the data and instructions required to operate the specific hardware components of the hardware 300. For example, the hardware abstraction layer 314 defines the 5 counter values required for the implementation of the synthesizer 132 ( see Figure 1) at the frequency in

  question for communication systems defined by system control units.

  Figure 4 illustrates a method of operating the

  Figure 3 communication device in conjunction with a plurality of autonomous communication systems.

  Figure 4 illustrates the operation of the communication device to locate all the available communication systems with which it can communicate15 (using its first, second and shared resources) and the timing with as many systems as possible. As many exchanges between a base station and a mobile station are periodic (i.e. control signals and time intervals), the communication device20 must divide its total activity time between these periodic exchanges and other communications planned until

start of a call.

  In Figure 4, the communication device 102 first determines which systems are active in the plurality of autonomous communication systems. In Step 400, a variable x is initialized and in Step 402, the communication device 102 determines whether the system x is present and active. This is done, for example, by searching for control channels defined by system x or by locating a control signal (in a CDMA IS-95 system). If the system x is present, the communication device 102 is synchronized to a base station of the system x according to any known method and, in Step 406, increments the variable x. If no system x is located, the variable x is incremented. AT

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  in Step 408, the variable x is compared to a limit. If the limit is not reached, control returns to Step 402 to search for additional systems. If the limit is reached, the command goes to Step 410. It will be understood that other loop commands in parallel with the use of a variable can be used when

  research of all available systems.

  After locating the systems, the communication device 102 locks onto as many active communication systems as possible. In Step 410, we initialize a variable y. The variable y corresponds to the active communication systems identified in steps 400 to 408. In Step 412, the communication device 102 is wedged on the system y. Preferably, this is done during free line time on other systems when shared resources of the communication device 102 are available. For example, if the communication device 102 is in communication with a TDMA communication system, the registration of a new system occurs there during a time interval of the TDMA system not assigned to the communication device 102

  when shared resources can be reassigned to the registration process.

  The registration generally includes an exchange of identification information between a mobile station such as the communication device and the communication system. Registration information is used by the communication system to locate and identify the mobile unit. So that the calls can be routed efficiently to a particular mobile station, each mobile station generally locks its position on the nearest base station. An incoming call is then routed by the network control unit to this base station, which then establishes a

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  radio communication with the mobile unit to end the call. In Step 414, if necessary, the system supervisor 304 (see Figure 3) plans his activity time with the system y. The system supervisor 304 negotiates the communication aspects between the

  communication and the systems in which the communication device is registered. For example, if the system y is a TDMA system, the system supervisor 30410 negotiates time intervals for communication between the communication device 102 and the system y.

  Other communication aspects that can be negotiated include channel frequency. Negotiation is required because the communication device 102 may already be registered in other systems and has allocated parts of its communication resources or active to these systems. In an optional embodiment, the system control unit of the communication device 102 for the system schedules a time there with the system supervisor 304, without negotiation with the system itself, taking into account only the total activity time of the

  communication device 102. This has the advantage of limiting communication with the system y, reducing the traffic of the system and saving the battery power25 of the communication device 102.

  After planning the activity time for the system y, the system supervisor 304 updates in Step 416 a system priority table. The system priority table defines the planned communication times and the relative priorities between the plurality of communication systems. For example, if the communication device 102 is configured to communicate on an Iridium system and a GSM system, the system supervisor 304 can establish a priority as follows:

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  On the central GSM system, priority is:

1) GSM

2) Iridium.

  When traveling on a GSM system, the priority is: 1) Iridium

2) GSM.

  The priority decision receives factors such as the relative cost for air time, etc. Therefore the

  communication device 102 prioritizes the registered systems for establishing communication.

  In Step 418, the communication device 102 determines whether sufficient free time remains in its total activity time to support communication with another system. If yes, in Step 420, the variable is incremented there and another active system is connected to

  the record. If not, the communication device 102 begins monitoring the registered systems for call activity.

  Figure 5 is a flow diagram illustrating the operation of the communication device 102 of Figure 3. The call search begins at Step 500. In Step 502, the communication device 102 waits for call activity. In Step 504, the communication device 102 determines whether call activity has been detected. Call activity may be an indication

  incoming call activity received from a communications system or an attempt to make a call by a user pressing keys on a keyboard. If call activity is detected, in Step 506, the call is processed and control returns to Step 502.

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  If no call activity is detected in Step 504, the communication device 102 then determines whether the real time, as kept by its integrated clock, corresponds to a planned event time. A planned event time5 corresponds, for example, to an assigned time interval on a recorded communication system or to a recording test time with a system. Scheduled event times are times when the communication device 102 is scheduled to communicate with one of the plurality of communication systems. If this is not currently a planned event time, the

command returns to Step 502.

  If the communication device 102 should not respond, the system control unit then requests in Step 514 (like the first system control unit 306 in FIG. 3) priority A from the system supervisor 304 (see Figure 3). If priority A is not granted, the system supervisor 304 schedules in Step 518 the event request response if possible and the control returns to Step 502. If priority A is granted in Step 518, the communication device 102

  begins communication on system z in Step 520. Communication continues until the end in Step 522. When communication is complete, priority A is released in Step 524 and control returns to l 'Step 502.

  Figure 6 is a flow diagram illustrating the operation of the communication system and the communication device of Figure 1. Figure 6 illustrates the steps followed to enter and exit an inactive state, both on the communication device. communication and on a communication system. In Figure 6, the operation of the communication system (such as a base station in a cellular ground system or a satellite transceiver in a satellite communication system) is shown on the side

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  left and the operation of the communication device (such as a multimode cell phone) is shown on the right side. In Step 602, communication is established

  between the communication system and the communication device. A similar step occurs in Step 604 for the communication device.

  In the illustrated embodiment, entry into the inactive state is initiated by the communication device. A user input is provided in the idle state or an automatic determination by the communication device of the time and duration of the input. User input can occur, for example, if a user knows that he is going to fly and will be unreachable by any ground system15 and even any satellite system. The user can define an inactivity start time and an inactivity duration which must correspond to the flight time. In Step 606, the communication device checks the user input. If the user input is present, the communication device receives in Step 608 from the user the inactivity start time and the inactivity duration. If no user data is provided, the communication device determines in Step 610 the start time of the inactivity state and the duration of this state. The communication device can do this, for example, in response to a slower time interval on another system. In such a way that the communication device is ready to receive its time interval on the other system, it determines the instant and the duration of the time interval. In an optional implementation mode, only the duration

  of inactivity corresponding to the duration of the inactivity state is determined.

  In Step 612, an inactivity message is transmitted from the communication device and in Step 614, the

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  Inactivity message is received from the communication device on the communication system. The inactivity message indicates that the communication device will be unavailable for a predetermined period of inactivity time5. The inactivity message can include any suitable information, namely the duration

  of inactivity, the start time of inactivity and a simple request to enter the inactive state.

  In Step 616 and in Step 618, the communication system and the communication device negotiate the parameters of the idle state. For example, if this

  is not previously specified, the negotiated parameters include the idle time and the idle start time. In an optional embodiment, no negotiation occurs and the communication device dictates the parameters of the idle state.

  In Step 620, at the instant of start of inactivity, the communication system interrupts the communication with the communication device. In Step 622, a similar procedure is performed by the communication device. In the communication system, the communication link can be kept active for example by not reassigning the communication link time interval or by continuing to provide control and timing signals to the communication device. Optionally, to increase the capacity of the

  system, communication resources such as time interval and frequency can be reassigned when the communication device is inactive.

  An advantage in informing the communication system that the communication device will be in idle mode is the conservation of the resources of the system. If the system knows that the communication device is inactive, the system does not

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  no waste of resources, for example when trying to call the communication device using an incoming call. Then, in Step 624, the communication system determines whether there is an incoming call planned5 for the communication system. If yes, in Step 626, the communication system provides an informational message in response to the incoming call received during the predetermined period of inactivity time. In an optional embodiment, part of the user information 10 entered in Step 606 may include the information to be provided in the information message. The message can

  simply inform the sender of the user's unavailability or may cause the sender to leave a voicemail message or provide some other suitable message.

  After providing the message or if no incoming call has been detected, the communication system determines in Step 628 whether the time of inactivity of the communication device is exceeded. If yes, at Step 630, following the predetermined period of inactivity, the communication device completes the

  communication with the communication device.

  On the communication device, after interrupting communication with the communication system in Step 622, the communication device communicates with another communication system in Step 632. If the communication device includes shared resources, the shared resources are reassigned from communication with the communication system to communication with the other communication system. This may include selecting a different frequency band, using a different communication protocol, etc.

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  Communication between the communication device and the other communication system may be previously scheduled or may simply be a test for incoming calls. For example, the communication device can receive a time interval having control information (probably including a call identifying an incoming call) from another system. Optionally, the communication device may have detected the presence of the other system during a previous state of inactivity and is now trying to register with the other system for

the current state of inactivity.

  In Step 634, the communication device determines whether it is time to exit the idle state and return to communication with the communication system. In the illustrated embodiment, the communication device determines whether the communication on the other system is ended. In optional modes of implementation, the communication device could verify the end of the period of inactivity or some other suitable condition. In Step 636, the device

  Communication completes communication with the communication system.

  As can be seen from the above, the present invention provides a communication method and device for multimode communication with multiple autonomous communication systems. Individual resources are dedicated to communication on the respective communication systems. In order to minimize production costs, resources are shared between communications on respective modes. A system supervisor assigns priorities, plans and controls communication between the communication device and the autonomous communication systems. So the communication device can

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  access multiple systems even when traveling in

  different locations with different types of service.

  While a particular embodiment of the present invention has been illustrated and described, modifications can be made. It is therefore

  provided that the appended claims cover the whole

  of these variants and modifications coming into mind and

the scope of the invention.

27 2763462

Claims (20)

  1. A method of operating a communication device (102), the communication device being able to operate on a plurality of communication systems5 (104, 106), characterized by the following steps: - establishing (202) a first communication on a first communication system (104) using a first communication circuit (124) and a shared communication resource of the communication device; - detecting (208) a communication request on a second communication system (106), the second communication system being autonomous with respect to the first communication system; - putting the first communication into inactivity (224); and - establishing (214) a second communication on the second communication system using a second   communication circuit (126) and the shared communication resource of the communication device.   2. Method according to claim 1, characterized in that the request is created on the communication device.   3. Method according to claim 1, characterized in that the request is created on the second communication system.   4. Method according to claim 1, characterized in that the step of inactivity   includes placing the first communication circuit in an inactive state. 28 2763462   5. Method according to claim 4, characterized in that the step of establishing the first communication comprises the registration of the communication device in the first communication system and the step of establishing the second communication comprises the device registration   communication in the second communication system and in that the step of placing the first communication circuit in an inactive state includes removing the communication device from the first communication system.   6. Method according to claim 1, characterized in that the step of detecting a request   includes detecting (210) a scheduled communication time for communication on the second communication system.   7. A method of operating a communication device (102) on a plurality of autonomous communication systems (104, 106), characterized by the following steps: a) on the communication device, the determination (402) of the active systems in the plurality of autonomous communication systems; b) recording (412) with as many active communication systems as possible; and   c) controlling (422) the registered systems with respect to calling activity.   8. Method according to claim 7, characterized in that it further comprises a step of establishing (416), after the step of recording, a priority of the systems recorded to establish a communication. 29 2763462   9. Method according to claim 8, characterized in that it further comprises the following steps: - using the priority of the registered systems, the determination of a system with which it generates a communication; - the transmission of a communication on the system; and   - at the end of the communication on the system, repeating steps a) to c).   10. Method according to claim 9, characterized in that it further comprises a step, before   creation of communication, deletion on one or more other registered systems.   11. Method according to claim 7, characterized in that it further comprises a step of planning one or more communications with at   minus a system of registered systems.   12. Method according to claim 11, characterized in that it further comprises a step, before recording on an additional system, of determining that a sufficient time of inactivity   exists to support communication with the additional system.   13. Method for coordinating a communication between a communication device and a plurality of autonomous communication systems, characterized by the following steps: - determining the active systems from the plurality of autonomous communication systems; 2763462   - establishing communication between the communication device and at least some of the active systems, forming recorded systems; and - negotiation of the communication aspects for a communication between the communication device and the registered systems. 14. Method according to claim 13, characterized in that the communication aspects   include one or more time slots for communication between the communication device and a registered system.   15. The method of claim 13, characterized in that the step of establishing the   Communication includes recording on at least 15 of the active systems to form the registered systems.   16. Method for coordinating a communication between a communication system and a communication device, the communication device being configured to communicate with a plurality of autonomous communication systems comprising the communication system, characterized by the following steps: - on the communication system, establishing communication between the communication system and the communication device; the reception of an inactivity message from the communication device, the inactivity message indicating that the communication device will be unavailable for a predetermined duration of inactivity time; 31 2763462   - the interruption of a communication with the communication device; and - following the predetermined duration of inactivity time, the completion of the communication with the communication device. 17. The method of claim 16, characterized in that it further comprises the following steps: - negotiation with the communication device of an inactivity start time to enter an inactive state; and   - at the time of the start of inactivity, the interruption of communication with the communication device.   18. The method of claim 16, characterized in that it further comprises a step of providing an information message in response to   incoming calls received during the predetermined period of inactivity time.   19. The method of claim 16, characterized in that it further comprises: - on the communication device, the reception of a user input defining the predetermined duration of inactivity time; and transmitting the predetermined duration of time   communication system inactivity.   20. The method of claim 19, characterized in that it further comprises the following steps: 32 2763462   - on the communication device, the reception of a user input defining an inactivity start time; - the transmission of the start of inactivity instant to the communication system; and - on the communication system, at the time of the start of inactivity, the interruption of communication with the communication device.